A creature
emerges from the moon's surface and quickly flies down
to Earth. Upon landing, the creature is spotted and
dubbed Redmoon. Almost simultaneously, another monster
appears from Habu Island, located in the Okinawa chain.
This second creature is given the name Erabus.

The Japanese Self Defense Force feels that the appearance
of the two kaiju is a perfect opportunity to lead the
monsters together so that they will kill one another.
The plan is a success, as they are able to lure the
two monsters together; however, instead of fighting
the two monsters mate, as it's discovered that Redmoon
and Erabus are male and female of the same species.
Shortly after mating, Erabus gives birth to small creature
called Hafun.

While the SDF is trying to figure out what to do with
with the creatures, Hafun is kidnapped by an entrepreneur
with the hopes of displaying the creature for profits.
Unfortunately, Hafun dies in the process of being moved,
causing Redmoon and Erabus to go berserk and begin laying
waste to the cities in Okinawa. However, Godzilla arrives
on the scene and manages to defeat both Redmoon and
Erabus, putting an end to the destruction.

Background

The film
was planned as part of the yearlong celebration
of Tsuburaya Productions' 10th Anniversary in 1972.
Tsuburaya Productions approached Toho with the idea
of creating a new film with Toho's most popular,
and Eiji
Tsuburaya's most famous, creation: Godzilla.
Toho gave the project the green light, and agreed
to loan Tsuburaya Productions' a Godzilla suit.

Tsuburaya Productions' assembled a team for the
film which consisted of Noboru Tsuburaya and Toyowaki
Awa as producers, Shokei Tojo as director and Kazuo
Sakawa as the Special Effects director. Reportedly,
the Godzilla suit for the movie was going to be
the one from Son
of Godzilla (1967), probably so that Toho
could continue to use the Destroy
All Monsters (1968) suit in their own productions.
Unfortunately, the project never saw the light of
day in its current form. Over time, though, it was
heavily altered and repackaged beyond recognition
as Daigoro
vs. Golaith (1972), with Toho taking simply
a distributor role and Tsuburaya Productions' producing
in the final product.